<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    function* getData() {
      console.log('开始获取数据A')
      yield setTimeout(() => {
        console.log('获取数据A成功')
        d1.next()
      }, 2000)

      console.log('开始获取数据B')
      yield setTimeout(() => {
        console.log('获取数据B成功')
        d1.next()
      }, 2000)

      console.log('开始获取数据C')
      yield setTimeout(() => {
        console.log('获取数据C成功')
      }, 2000)
    }
    let d1 = getData()
    d1.next()
  </script>
</body>

</html>